An obligate parasite, or holoparasite, is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host.
Part of the Andes mountain range, Aconcagua is the second highest of the Seven Summits, behind only Mount Everest in Asia. At 22,837 feet (6,961 meters), not only is it the highest mountain in South America, it is the tallest peak in all of the Americas as well as the Southern and Western Hemispheres.
Mauna Kea (in Hawaii) is the world's tallest mountain peak. When measured from the ocean floor to its summit, it's 33,476 feet tall (10,204 meters), but only its top 13,803 feet (4,207 meters) extend above sea level.